Method for treating hides



Patented J an. 7, 4 1930 PATENT OFFIC DAVID L. LEVY, OF LYNN, MASSACHUSET'I,

METHOD FOR TREATING HIDES N Drawing. Application filed May 20,

This invention relates to an improvement in a method or process for treating hides.

The fundamental object is to increase the yield without detriment to the leather, with 5 the ultimate result that the leather is greatly improved.

Heretofore a process has been developed in which the stretched hide fastened to a frame of wood or other material, is submerged in a vat or tank containing tanning liquor of the desired character, where itis permitted to remain until the process of tanning is complete. This process was evidently devised with the intention of increasing the yield by maintaining the stretched condition of the leather during the tanning, and thus preventing shrinkage. For obvious reasons this d creased the quality of the leather, and the practice was otherwise uneconomical and impracticable.-

lVith my process, I increase the yield, and at the same time greatly improve the product, and otherwise obviate the objections to the herein referred-to process. In my process, there are three main steps in the procedure Instead of tanning after the hide is stretched, and while in a stretched condition, I first tan it in a vat or tank containing chromimn compounds, alum, common salt, 20 and acid, in suitable proportions, for the usual length of time. After this first tanning process, I stretch the leather and fasten it on a frame in the time-honored way.

Then the second step in my process is to prezts vent the hide (after removal from the frame) from shrinking back to its original or substantially its original proportions; and this is accomplished by putting it through a second tan, adding to the tan liquor a certain :0 amount of common salt varying according to the conditions and nature of the hides being treated. I

Following this, the third step is a follows z-Vhile fat liquoring in the drum heretofore using oil, I add a large percentage of glycerin to the oil in proportions of approximately one part of glycerin to two parts of oil, this being subject to variation according to the nature and condition of the hide. Glycerin nourishes the leather, which is the 1927. Serial. No. 193,067.

.desideratum, bringing the fibre closer to the grain, and with the result that while degreasing the hide to make it into patent leather, the oil is removed but the g1 cerin remains in the leather, as it cannot e extracted. The result is, it gives the product a velvety or silky feel, and at the same time strengthens the leather.

Thus I get the advantage of the increased yield by maintaining the stretched condition without the slightest injury or detriment to the leather, and, on the contrary, produce a greatly improved product.

I claim:

1. An improved. process for treating hides, which consists in first tanning, stretching, and fastening a hide on a frame, then giving it a second tan to which is added a certain amount of salt which varies according to the condition and nature of the hide being 7 treated. with the effect of preventing shrink v ing of the hide and maintaining its stretched condition, and finally while fat-liquoring in a drum containing oil, adding glycerin,

which latter has the effect of nourishing the leatherp-trnd remaining init after the oil is removed, thereby strengthening the leather, and at the same time imparting a velvety or silky feel thereto.

2. The process of treating leather includ- (,0 ing successively tanning it in a vat, stretching it after removal from the vat, tanning it in a liquor containing common salt, and thereafter fat-liquoring it in a drum containing oil and glycerin.

3. The process oftreating leather including tanning it in a liquor containing common salt, and thereafter fat-liquoring it in a solution containing glycerine. 1

4. The process of treating leather including tanning the hides and stretching the same, tanning the hides in a liquor contain- "ing common salt, and thereafter fat-liquoring them in a solution contaimng glycer ne.

In testimony whereof I affix my signature.

DAVID L. LEVY. 

